Which protocol is used by the ACI fabric to learn the location of ESX hosts?

Which protocol is used by the ACI fabric to learn the location of ESX hosts?
A. Council of Oracles Protocol
B. Link Aggregation Control Protocol
C. Link Layer Discovery Protocol
D. Cisco Discovery Protocol

Correct Answer: C
Explanation/Reference:
Explanation:
Discovery of Ports to Which VMware ESX Hosts Are Attached

In the example in the figure:
The AEP must be mapped to the ports.
The VMware ESX host discovers the neighbors through LLDP and communicates this information to VMware vCenter, which in turn provides it to Cisco APIC
Reference: http://www.cisco.com/c/en/us/solutions/collateral/data-center-virtualization/application-centric-infrastructure/white-paper-c11-731960.html